Up until the '20s, American football players sported wool jerseys on the field. Uncomfortable, itchy, and prone to shrinking in the wash, a new material was needed—and loopback cotton was the answer. Named for the air-trapping "loops" on the inward face of the fabric, loopback is an incredible insulator—super-soft on the inside and tough enough for the pitch on the outside. The Midweight Terry Half-Zip builds off this century-plus legacy with garment-dyed cotton for a softness you won't want to take off. It's also ribbed at the cuffs and hem for added comfort and durability. Last but not least, the opening has a reliable YKK zipper that comes up to meet a classic mock neck collar.